I'm guessing they do it, when they don't have to ride horses the next day.
Planning for the act then and now Then: find a safe place hidden from prying eyes, near water. Tie up horses, lay out blankets, light a fire(protect against wolves so your butt won't be eaten) then good to go. Now: The bedroom..... and it's home, home on the range where the deer and antelope play........
WHAT THEY JUST RUB?! THEY NEED MORE THAN JUST RUB (づ ̄ ³ ̄)づ